Apparatus for heating liquids.



Patented July 29, 1902.

J. FLIEGEL.

APPARATUS FOR HEATING LIQUIDS.

(Afaplication filed Aug. 22, 1901.)

(No Model.)

wlmsssesz 9mm! IUTORNE vs NrTEn STATES PATENT OFFICE.

JOSEF FLIEGEL, OF MALLMITZ, GERMANY.

APPARATUS FOR HEATING LIQUIDS.

SPECIFICATION forming part of Letters Patent No. 705,745, dated July 29,1902. Application filed August 22, 1901. Serial No..'72,909. (No model.)

To all whom it may concern: h

Be it known that I, J OSEF FLIEGEL, manufacturer, a subject of theGerman Emperor,

and a residentof SprottauerChausse, Mallmitz, in the Empire of Germany,haveina vented a certain new and useful Improved Apparatus for HeatingLiquids, Especially Milk, of which the following is a clear, full, andexact description.

The invention relates to improvements in such apparatus for heatingliquids, especially milk,to a germ-destroying temperature, according towhich the liquid to be heated flows through a series of chambers.

The invention has for its objectto effect a thorough mixture of theliquid to be heated, and therebya uniform heating of the same; also, toprevent the liquid contained in the apparatus from coming in contactwith the external air in order toavoid loss of heat and a renewedinfection of the liquid by micro-organisms. In known apparatus of thesaid kind the liquid is either passed without pressure throughoutwardly-opening chambers or the heating-chambers are closed and theliquid pressed through the same by meansof a pressure-pump; Both kindsof apparatus show material disadvantages. In apparatus having closedheating-chambers a thorough mixture of the liquid is prevented by thepressure necessary for feeding the liquid through the said chambers. Theliquid completely fills up the chambers through which it passes andflows into aclosed column through these chambers, so that movementscausing the mixture cannot takeplace within the liquid; but theparticles of liquid coming in direct contact with the walls of theheating-chambers become more heated than the other particles, thuseasily causing the liquid to become overheated, and consequentlyslightly burned, whereby especially milk re: ceives a disagreeabletaste. In apparatus having open heating-chambers the contact with theexternal air, however, causes a detrimental cooling of the liquid andthe danger of a renewed infection.

In order to avoid the drawbacks which are present in connection withknown apparatus, the'present invention contains the arrangementof anoutwardly-closed inflow-chamber,

which is only provided with an inlet socketpiece whose crosssection canbe so proportioned that the liquid can pass into the apparatus withoutallowing of the admission of external air into the apparatus to aconsiderable extent.

In order to prevent a pressure of the liquid in the heating-chambers,each of these chambers is provided with one or more air-exhaustchannels,whereby the waste steam of the heated liquid can escape withoutthe external air entering the apparatus.

Bydischarging the waste steam the liquid need not completely fill up thechambers through which it passes, so that there are free spaces whichallow of a separation and a thorough mixture of the liquid.

A further part of the invention consists therein that the air-exhaustchannels in which the heatingof the liquid takes'place lead into achamberfor instance, the inflow-charm her-located in front oftheaforesaid chambers, thus enabling the waste steam of the heatedliquidto be utilized for preliminary heating. These air-exhaust channelsare preferably so provided that the already-heated liquid cannot mixwith the less heated liquid.

' A further development of the invention is the arrangementof acollecting-chamber in which the heated liquid enters after it has passedthrough the heating-chambers and from which the hot liquid can bedischarged through a cock or the like without mixing with the non-heatedliquid.

The combinations of the invention are shown in the drawing by way ofexample.

The apparatus shown is so arranged that the liquid to be heated flowsthrough the ap paratns in an opposite direction to the heated liquid.

The figure in the accompanying drawing shows the apparatus in alongitudinal section.

The apparatus consists of an outer cylindrical vessel 1, which isrigidly mounted on a bottom frame 2 and provided with anoverilow-channel 23, passing around the same. \Vithin the vessel 1 isprovided a cylinder 4-, which is mounted by blocks 50 upon the cylinder1 and covered by an upper lid 5. In the vessel 4 is provided a rotatingagitator, which consists of an upper plate 6 and downwardly-directedconcentric annular pieces 7, rigidly connected with such plate, theseannular pieces 7forming annular chambers. A tube 8 of the plate 6loosely passes into a tubular piece 8' of the cover 5, through whoseaperture or slot 9 the feed of the milk to be heated is effected in asuitable manner. The object of the tubular pieces 8 and 8 is thatthrough the same the vapors produced in the milk escape in the directionof the dotted lines a: into the milk admission or inlet chamber. Theagitator is connected by a support 10, having a lower ring 11, to abifurcated arm 12, whose shaft 13, with ball step-bearing 13, is drivenby a rope pulley 14 or in any other suitable manner, so that theagitator is also rotated thereby. The agitator is connected to thesupport 10 in such a manner that the ends of the bifurcated arm 12engage behind two projections 11 in the rotating direction of the valve11 or support 12, and thus take with them the support 10 and also theagitator 6.

Between the annular pieces 7 is provided in the inner annular chamber asteam-heating body 16, communicating with the steam supply or inlet pipe15 and toward the exterior chambers 17, with lower free communicationfor allowing of the heated milk and milk to be heated to flow inopposite directions through the apparatus, which is effected by theannular pieces 18 of the vessel 1 in a manner to be more fully explainedlater on. Air-exhaust pipes 19 open above and below and, extendingthrough the bottom of the vessel 1, communicate with the chambers 17.There are also provided in the upper plate 6 of the agitator, betweenthe annular pieces 7, pipes 20 for discharging the vapors. The pipes 19and 20 are so high that the milk passing through or fed into theapparaus cannot pass into these pipes.

The pipes 20 are provided so that the vapors can issue from the chambers7 without milk passing therein, which does not take place, because themilk poured through 9 lies quite flat on the bottom. The pipes 19 arearranged at such a height that their outlet is not reached by the milkcontained in the ves sel 17 and passing over the part 18, while vaporspass freely from 17 through the pipes 19. .Of these pipes 19 so many areprovided as required for conducting the vapors from the milk. In thepresent case only those on the right side are indicated in the drawingfor the sake of clearness, while those on the left side are omitted.They are fixed in the annular pieces 18.

The interior of the apparatus is formed by a collecting-chamber 21,whose upper ring 22 receives the conical ring 11 of the support 10 ofthe agitator and is open toward the bottom to admit of a return of theheated milk in an opposite direction to the flow of the milk to beheated in the apparatus. The admission of the milk from theheating-chamber 23, surrounding the collecting-chamber in the upper partlaterally and above, is effected through a comparatively narrow open ing24 in the disk of the ring 11, which aifords a seat for a valve 25 of ahollow spindle 26, operated by a hand-wheel 27, whereas the second valve28 on opening the valve 25 shuts off the socket 8 of the plate 6 of theagitator. The hand-wheel and also the spindle 26 are provided withsuitable threads whereby when turning the hand-wheel the spindle 26 israised with the valves 25 and 28. The valves 25 and 28 are rigidlyfixed. If the spindle 26 is screwed downward, the valve 25 shuts 0d theadmission of the milk to the receiver, whereby according as this valveis adjusted lower the circulation of milk to the receiver is regulated.It the spindle 26 is screwed upward, the valve 28 shuts off the pipe 8to the milk-chamber, whereby by means of pipe 32 air is pumped out ofthe milkchamber, or the milk which is still contained in the apparatusafter the pipes 20 and 19 are plugged is pumped out through pipe 32,whereby all the milk can be discharged from the apparatus. In thetubular spindle 26 is inserted a thermometer 29, whereby the averagetemperature of the heated milk fed to the collecting-chamber 21 can beascertained. In the same manner the heating-chamber 23 is accessiblethrough a pipe 31, introduced from below and containing a thermometer30.

The milk-heating apparatus operates as follows: By means of a milk-pumpor a collecting vessel the milk to be heated is fed through the aperture9 of the lid 5 to the apparatus and passes to the top 6 of the agitator.From this cover the milk is fed in the direction of the arrows indicatedby full lines to the separate heating-chambers 17 between the annularpieces of the agitator and the fixed vessel 1 and finally to thesteam-heating body 16. The milk then enters the wide heating chamber 23,which surrounds the central collecting-chamber 21 laterally and above,in order to rush, after opening the thermometer-valve 25, through thecomparatively narrow opening 24 into the collectingchamber 21.Consequently a thorough mixture of the heated milk takes place, so thatthe average temperature can be ascertained with certainty. The mixtureis all the more complete, as the milk issues into the collecting-chamberwithout being subjected to pressure. The milk remains in thecollectingchamber 21 for a sufliciently long period so as to bethoroughly sterilized by the action of the heating-body 16. Furthermore,this collecting-chamber and the heating of the milk therein allow of aheating temperature below boiling-pointnamely, below 100 centigradeto beobserved, since the germ-destroying action in connection with infectiousdiseases, such as flags and blackleg, is already attained at heatmaintained for about ten minutes. By this method of heating the milk theboiling taste of the sterilized milk, which is so detrimental to themilk trade and the making of butter, is avoided. The propersterilization of the milk is especially insured on account of the factthat the heated milk in the collecting-chamber 21 is protected againstcooling down and can therefore be maintained at a high temperature for acertain length of time. the agitator serves at the same time for thefurther continuous mixture of the milk in the collectingchamber, so thatan absolutelyuniform temperature of the milk can be relied upon and anoverheating by the heating-bod y is prevented. The sterilized milkpasses from the collecting-chamber 21in an opposite direction to theincoming milk into the separate chambers 17, gives oft its heat to thefed milk to be heated in order to pass out of the vessel 1 above in aconsiderably-cooled state and to enter the overflow-channel 3 of thesame. The milk is not discharged from the apparatus through piping, asin connection with known apparatus; but for avoiding any pressure itpasses into an overflow-channel above at the edge of the vessel 1, fromwhence it is fed through a delivery-channel to the cooler, centrifugalapparatus, or the like. (Not shown.)

The possibility of easily and conveniently cleaning all parts of suchapparatus is insured by the fact that the cover or lid 5 can he readilyremoved by a winch or the like. The agitator can be taken out in thesame manner, and the cylinder 4; can also be removed for uncovering thecylinder 1, with its annular pieces 18, after loosening the connectionsfor the steam and waste-water pipe.

A material advantage of the apparatus consists in the fact that theentire milk contained in the vessel 1 is sterilized, so that aftertaking the apparatus to pieces the milk is ready for use,while inconnection with known constructions the milk still contained in theapparatus is considered as insufficiently sterilized on account ofmixing the heated with the nonheated milk when the apparatus is notworking. Furthermore, it is of moment that all of the milk contained inthe vessel 4: is sufliciently heated and that at the end of the processno milk remains which has not reached the necessary temperature and beenmaintained at such temperature for a sufficiently long period. For thispurpose a pipe 32 is provided at the top 6 of the agitator. If the lastportion of fresh milk has been passed into the apparatus, milk willremain behind in the lateral chambers 17, according to the principle ofcommunicating pipes, which is not yet heated and does also not flowfurther. After the cover or lid 5 of the apparatus has been removed, thepipe 32 is put into commu nication with an air-pump and the mechanism ofthe agitator previously thrown out of gear. The air-exhaust pipes'20 aretightly closed by The driving-fork 12 for pipe 26 fixed against thelower edge of the socket 8 by the hand-wheel 27 for shutting 0E theformer. If the air-pu mp is now operated, the milk contained in thelateral chambers 17 will be sucked or drawn toward the middle of theapparatus. The collecting-chamber 21, which before the suction throughthe airpump has been emptied by the discharge-cock 33, whereby the milkissuing from the cock can be passed directly upon the cooler, isprovided at the pipe 31 with a valve 34. If this valve is opened beforethe suction takes place, the milk passes from the chamber 17 after being fed over the heating-body 16 and heated by the same, into thecollecting-chamber 21 and remains therein untilit is sterilized. Thismilk can also be discharged through the cock 33. In this manner it ispossible to properly sterilize the very last portion of milk containedin the apparatus.

Having now particularly described and ascertained the nature of the saidinvention, I declare that what Iclaim, and wish to secure by LettersPatent, is-

1. In combination, an outer vessel 1 having the annular pieces 18extending up there= from, a cylinder 4 extending down into the vessel 1and having chambers 17, the walls of which fit over the annular pieces18, an agitator having downwardly-extending annular pieces 7 extendingbetween the walls of the chambers 17, a heating-body 16, acentrally-arranged receiving-chamber 21 connected with the passagesformed between the walls of the chambers 17 and the depending pieces 7of the agitator, said receiving-chamber having an outlet connecting withthe passage formed between the walls of the chambers 17 and theannularpieces 18 of the vessel 1, said agitator having a horizontal diaphragmor top whereby the milk is directed to the passage between the chambers17 and the agitator, the said vessel 1 having an outlet for the milk andmeans for rotating the agitator, substantially as described.

2. In combination with the vessel 1 having the annularupwardly-extending pieces 18, a cylinder 4,- having the annular chambers17, the'walls of which fit over the annular pieces 18 to form acircuitous milk-passage, agitator means and air-exhaust pipes 19 open ata point above the upper edge of the pieces 18 within the said circuitouspassage, substantially as described.

In witness whereof I have hereunto set my hand in presence of twowitnesses.

JOSEF FLIEGEL.

Witnesses:

CARL ZOSEL, HERMANN BARTsoH.

